1. Field of the Invention
This invention relates to a process for separating a polymerization catalyst from a polymer. More particularly, this invention relates to a method for removing certain lithium compounds from a polymer comprising a conjugated diolefin and/or a monoalkenyl aromatic hydrocarbon compound.
2. Prior Art
Heretofore, several methods have been proposed for separating lithium compounds from a polymer, particularly a conjugated diolefin polymer. In general, these methods involve contacting the polymer and lithium containing composition with water and/or an acid. A principal problem associated with these methods is that each introduces an impurity to the polymer which must be removed before the polymer is suitable for at least most end use applications. These methods, then, add a rather complicated separation step to the processes. While the separation processes may be reasonably successful they frequently result in at least a small amount of impurity in the polymer composition. Also, the separation step is a rather complicated step in preparing the polymer composition for its various end use applications. The need, then, for a process which will separate certain lithium compounds from a polymer comprising a conjugated diolefin and/or a monoalkenyl aromatic hydrocarbon compound without introducing impurities thereto and without introducing a complicated "cleanup" or purification step is believed to be readily apparent.